The sum of the first ten terms of an AP is four times the sum of the first five

The sum of the first ten terms of an AP is four times the sum of the first five terms, then the ratio of the first term to the common difference is

2) If the third term of an AP is 12 and the seventh term is 24, then the 10th term is

3) If the first term of an AP is 2 and common difference is 4, then sum of its first 40 terms is

4) Common difference of sequence 5,8,11,14,… is

5) 1,8,15,22,29,36,… is